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Description
Aerodynamic source localization is conventionally performed by reconstructing acoustic source distributions from real or virtual microphone-array signals after propagation to the far field. Delfs and Ruck [1,2] proposed a diffraction-filtering methodology that reconstructs the acoustically active surface pressure and an associated surface source quantity directly from simulated surface pressure, thereby localizing sources without beamforming or far-field propagation. Here, the methodology is implemented within a frequency-domain Ffowcs Williams–Hawkings (FW-H) framework and applied to wall-modelled large-eddy simulations (WMLES) of a NACA0012 airfoil at 0° and 6° angle of attack, computed with the MGLET solver [3,4]. A mesh-convergence study identifies a converged surface-pressure solution, from which surface source distributions are reconstructed for both angles of attack. As an independent localization reference, conventional delay-and-sum beamforming is applied to microphone cross-spectral matrices synthesised with the in-house FW-H solver FWH-next and processed in Acoular [5,6], using the CFD surface as a common scanning grid. The reconstructed maps identify the trailing edge as the dominant source, resolve finer spatial detail than beamforming, and preserve the radiated far-field spectrum despite suppressing the surface pressure by up to about 40 dB.